Objects for Representing the Federal States of Nigeria

states(states, gpz = NULL, all = TRUE, warn = TRUE)

is_state(x)

as_state(x)

# S3 method for states
print(x, ...)

# S3 method for states
c(...)

# S3 method for states
[[(x, i, exact = TRUE)

# S3 method for states
[(x, i)

# S3 method for states
na.exclude(object, ...)

Arguments

states: A character vector with strings representing one or more States of Nigeria. If missing, the function will return a states object containing all the States.
gpz: NULL (the default) or, case insensitively, one or more of the following strings: "nc", "ne", "nw", "se", "ss" and "sw" (see "Details").
all: logical; whether to include the Federal Capital Territory (FCT) in the result.
warn: logical; issue a warning when one or more elements are not actually States (i.e. they were misspelt).
x: For is_state a vector to be tested. For as_state, a string representing a State that shares its name with one of its Local Government Areas.
...: Arguments used for methods. See documentation of generic for details.
i, exact: See help file for ?Extract
object: An object of class regions

Value

The States of Nigeria as a whole or by zones, as an S3 object of class states. is_state returns a logical vector.of same length as the input. If the input object is not even of type character, return the object unaltered, with a warning. In the case of as_state, an object of class states.

Details

gpz represents a geopolitical zone which, in the Nigerian context, is a national subdivision that groups contiguous states that bear certain socio-cultural and political similarities. Historically, they arise from sub-national administrative divisions known as 'Regions' that existed at the time of the country's independence. There are at present 6 such zones - North-Central, North-East, North-West, South-East,South-South and South-West.

For is_state, An element-wise check of a supplied vector is carried out. To test an entire vector and return a single boolean value, functions such as base::all or base::any should be used (see examples).

Note

is_state throws a warning, when a missing value is among the elements. It works only for atomic vectors, throwing an error when this is not the case or when NULL is passed to it. This design decision was made to allow rapid iteration through data frames without interruption, since spelling mistakes tend to be common.

Examples

states()  # lists names of all States
#> States
#> ------ 
#> - Abia
#> - Adamawa
#> - Akwa Ibom
#> - Anambra
#> - Bauchi
#> - Bayelsa
#> - Benue
#> - Borno
#> - Cross River
#> - Delta
#> - Ebonyi
#> - Edo
#> - Ekiti
#> - Enugu
#> - Federal Capital Territory
#> - Gombe
#> - Imo
#> - Jigawa
#> - Kaduna
#> - Kano
#> - Katsina
#> - Kebbi
#> - Kogi
#> - Kwara
#> - Lagos
#> - Nasarawa
#> - Niger
#> - Ogun
#> - Ondo
#> - Osun
#> - Oyo
#> - Plateau
#> - Rivers
#> - Sokoto
#> - Taraba
#> - Yobe
#> - Zamfara 
states(gpz = "se")  # lists States in South-East zone
#> States
#> ------ 
#> - Abia
#> - Anambra
#> - Ebonyi
#> - Enugu
#> - Imo 
all(is_state(naijR::states()))
#> [1] TRUE
is_state(c("Maryland", "Baden-Baden", "Plateau", "Sussex"))
#> [1] FALSE FALSE  TRUE FALSE

# With coercion
kt.st <- states("Katsina")  # Ensure this is a State, not an LGA.
kt.lg <- suppressWarnings(as_lga(kt.st))
is_state(kt.st)             # TRUE
#> [1] TRUE
is_lga(kt.lg)               # TRUE
#> [1] TRUE

## Where there's no ambiguity, it doesn't make sense to coerce
## This kind of operation ends with an error
if (FALSE) {
as_state("Kano")
as_lga("Michika")
}